Purification and properties of trout gill AMP deaminase

The AMp deaminase has been purified 450-500 fold from 20,000 g supernatants from trout gill. The procedure comprised cellulose phosphate and DEAE-cellulose chromatography. The gill appeared to contain different isoenzymes as indicated by different chromatographic behavior on cellulose phosphate and different heat stabilities. The two major isoenzymes were compared with respect to their pH optima and the effect of temperature. ATP and inorganic phosphate. The pH opitmum is about pH 6.7 at low substrate concentration. A second optimum is found in phosphate buffer. The substrate saturation curve is hyperbolic, even in the absence of KCl or ATP. ATP is an activator of the enzyme in the absence of KCl, but is without effect in the presence of monovalent cations. Among the monovalent cations tested, Na super(+) is the most potent activator followed by K super(+) and NH super(+)d4.